Quantitative Acoustics Approach for Damage Detection in Hard Armor Protective Inserts

Abstract

The tap-test has long been a benchmark in non-destructive inspection of material systems, including the investigation of delamination effects in composites. In this research, tap-test related impact force variations in the (human) audible acoustic range (up to 20 kHz) are associated with damaged and undamaged hard armor protective inserts using an experimental approach. Damaged and undamaged states are determined a priori by Army quality inspections and further investigated by x-ray computed tomography (XCT), which are used to validate the presented approach. Digital signal processing of impact-echo type acoustics data is conducted to determine metrics that may differentiate between the damaged and undamaged states while providing hardware/software solutions to robustly identify damage locations. Funding for this effort is provided by the U.S. Army Program Executive Office – Soldier.